Strict diagnostic criteria (after Harding, 19812)
| Essential | Age of onset before 25 years |
|---|---|
| Progressive ataxia of gait and limbs | |
| Absent knee and ankle jerks | |
| Axonal picture on neurophysiology | |
| Dysarthria (if after five years from onset) | |
| Additional (present in over 66%) | Scoliosis |
| Pyramidal weakness in lower limbs | |
| Absent reflexes in arms | |
| Large fibre sensory loss on examination | |
| Abnormal ECG | |
| Others (less than 50%) | Nystagmus |
| Optic atrophy | |
| Deafness | |
| Distal amyotrophy | |
| Pes cavus | |
| Diabetes |